UNIT 4: Lumbar Puncture and Myelogram Flashcards
What is a Lumbar Puncture?
A procedure in which a needle is placed in the lower back between two vertebrae to collect cerebrospinal fluid
What is a lumbar puncture done for?
Fluid sent to the laboratory for testing
► Meningitis
► Guillain-Barre syndrome
► Multiple Sclerosis
► Cancers of the brain or spinal cord
► Lumbar Punctures may also be necessary to administer certain types of chemotherapy to the central nervous system that do not cross the BBB (blood-brain barrier)
Lumbar Puncture Room set up (done by Rad tech)
•Sterile tray
• Sterile gloves
• Sterile cleaning solution
• Lidocaine
• Spinal needle
• Syringes
• Razor
• Manometer
• Biohazard bag
• Labels for syringes
• Skin marker
• Tubing
• 3 way stopcock
• Sterile drape = surgical masks
► Fluoroscopy console set up for fluoro procedure
► Foot board on the table
► Table bucky in position at the foot of the bed
► Protective curtain NOT on for this procedure due to interference with sterile field
► Pillow placed in the middle of the table under the patient’s hips; prone
► Radiographer takes a history if possible and obtains informed consent
► Radiographer explains the procedure to the patient
Lumbar Puncture Procedure
► Patient put in a hospital gown and positioned on the fluoro table PRONE or in Lateral flexed position
► Some physicians may want patient rotated into a shallow LAO position
► Surgical “Time-out” procedure is performed by all personnel in the room
► Lower back exposed and cleaned using aseptic technique
► Radiologist gives a local anesthetic to numb the skin and muscle layer
► Radiologist uses fluoroscopy to guide a spinal needle into the subarachnoid space
► Confirmation of placement when CSF(CerebroSpinal Fluid) emerges from the end of the needle
► CSF allowed to flow naturally into vials OR gently aspirated by a radiologist
► Approximately 10 mL fluid is required for most laboratory testing
► Patient must lie flat for up to 2 hours after the procedure to ensure closure of the needle-hole and to prevent further leakage of CSF
Lumbar puncture results from lab take __ days
5
Lumbar Puncture risks
► Infection
► Spinal headache
► Back discomfort
► Bleeding
► Patients taking blood thinning medications are asked to withhold them prior to the procedure
What is Myelography?
General term to describe the radiologic examination of the CNS structures situated within the vertebral canal
How is a Myelography exam done?
Intrathecal injection of a nonionic, water-soluble contrast medium into the subarachnoid space by lumbar puncture
► L2-L3 disk space
► Cisterna magna between C1 and the occipital bone
► Often done in conjunction with CT
What is a Myelogram exam done for?
► Extrinsic spinal cord compression: herniated disk, fracture, or tumor
► Evaluation of the flow patterns of CSF(CerebroSpinal Fluid)
Myelogram Exam Room set up (done by Rad tech)
• Sterile tray
• Sterile gloves
• Sterile cleaning solution
• Lidocaine
• Spinal needle
• Syringes
• Razor
• Non-ionic water soluble Contrast media (ex: Omnipaque or Isovue)
• Skin marker
• Tubing
• 3 way stopcock
• Sterile drape
• Surgical masks
► Fluoroscopy console set up for fluoro procedure
► Foot board on the table
► Shoulder board on the table
► Table bucky in position at the foot of the bed
► Protective curtain NOT on for this procedure due to interference with sterile field
► Pillow placed in the middle of the table under the patient’s hips, prone
► Radiographer takes a history if possible and obtains informed consent
► Radiographer explains the procedure to the patient
Myelogram Procedure
► Patient put in a hospital gown and positioned on the fluoro table PRONE with the pillow under the abdomen
-Some physicians may want patient rotated into a shallow LAO position
► Surgical “Time-out” procedure is performed by all personnel in the room
► Lower back exposed and cleaned using aseptic technique
► Radiologist gives a local anesthetic to numb the skin and muscle layer
► Radiologist uses fluoroscopy to guide a spinal needle into the subarachnoid space
► Confirmation of placement when CSF emerges from the end of the needle
► CSF may be drawn out and sent for laboratory testing
► Approximately 9 to 12 mL of contrast is injected into the subarachnoid space
► After injection of contrast material, the needle is removed and the patient is positioned for spot imaging
► Trendelenburg position may be required for cervical imaging
► The patient should be instructed to extend chin as much as possible in order to prevent contrast from trickling into the space around the brain
► Several images may be obtained
- Cross table lateral
- AP/PA
- Erect
- Flexion/extension
► Patient taken to CT for additional imaging within approximately 10 to 30 minutes
► Patient held in department and asked to elevate head 30 to 45 degrees for up to 2 hours
Injections into the subarachnoid space are termed
Intrathecal injections
What modality has largely replaced myelography?
MRI
What type of contrast dose MRI use?
Gadolinium
What type of contrast does CT use?
Nonionic water soluble, omnipaque or isovue
